The correct order of boiling points of isomeric amines is

Options

A. tertiary gtsecondary gtprimary
B. secondarygt primarygt tertiary
C. primary gtsecondarygt tertiary
D. secondary gttertiary gtprimary

Answer

To determine the correct order of boiling points of isomeric amines, we need to analyze the structure of primary, secondary, and tertiary amines and their ability to form hydrogen bonds.

### Step-by-Step Solution:

1. **Understanding Amines**:
- Amines are classified based on the number of carbon atoms attached to the nitrogen atom.
- **Primary amine**: Nitrogen is attached to one carbon atom and has two hydrogen atoms (e.g., CH3-CH2-NH2).
- **Secondary amine**: Nitrogen is attached to two carbon atoms and has one hydrogen atom (e.g., CH3-CH(NH2)-CH3).
- **Tertiary amine**: Nitrogen is attached to three carbon atoms and has no hydrogen atoms (e.g., (CH3)3N).

2. **Hydrogen Bonding**:
- Hydrogen bonding is a significant factor affecting boiling points. The ability of a molecule to form hydrogen bonds increases its boiling point.
- Primary amines can form two hydrogen bonds per molecule (due to two hydrogen atoms attached to nitrogen).
- Secondary amines can form one hydrogen bond per molecule (due to one hydrogen atom attached to nitrogen).
- Tertiary amines cannot form hydrogen bonds because they have no hydrogen atoms attached to nitrogen.

3. **Comparing Boiling Points**:
- Since primary amines can form the most hydrogen bonds, they will generally have the highest boiling points.
- Secondary amines, with fewer hydrogen bonds, will have lower boiling points than primary amines but higher than tertiary amines.
- Tertiary amines, having no hydrogen bonding capability, will have the lowest boiling points.

4. **Boiling Point Values**:
- Based on the boiling point values provided:
- Primary amine: 323 K
- Secondary amine: 307 K
- Tertiary amine: 276 K

5. **Conclusion**:
- Therefore, the correct order of boiling points of isomeric amines is:
- **Primary > Secondary > Tertiary**
- This corresponds to the option C.

### Final Answer:
The correct order of boiling points of isomeric amines is: **Primary > Secondary > Tertiary**.